I just don't get the logic of waiving a guy, just to trade someone else to get him back.

I doubt that was the plan when they waived him. Yzerman probably gambled on passing him through waivers so he'd have the flexibility with the roster. With the re-acquisition, I'm guessing Yzerman really didn't like losing him to waivers.

This should also give you some idea of Bergeron's worth -- a 7th + a 4th liner.

Now... the real question in my mind is with Thompson, Crombeen, Tyrell, and Pyatt all under multi-year deals, I can't imagine Yzerman has any intention of extending Hall beyond this season. He is up for a new contract this summer, and normally I would think Hall is gone, but... surely the re-acquisition of him is to just fill out the roster until the end of the season, right? I shouldn't be reading any more into this, right?